Foaming of low density poly(ethylene-co-octene) resins by injection molding is the result of various reactions occurring during the process. This includes simultaneous decomposition of the chemical blowing agent and cross-linking of the polymer matrix during curing in the mold, followed by foaming after mold opening. Dynamicrheology as well as elongational viscosity were investigated for compounds prepared from resins with different melt indices and various cross-linking agent levels, and these results were linked to the morphology and density of the corresponding foams. Rheological requirements were finally defined quantitatively for this set of conditions.
1. Moulinié, P. and Woelfle, C. (1999). ANTEC 99 Proceedings, 2031–2034.
2.
2. Moulinié, P., Daigneault, L.E., Woelfle, C. and Gendron, R. (2000). ANTEC 2000 Proceedings, 1862–1866.
3.
3. Klempner, D. and Frisch, K.C. (1991). Handbook of Polymeric Foams and Foam Technology, p.442-442. Hanser Publishers, Munich.
4.
4. Vallés, E.M., Carella, J.M., Winter, H.H. and Baumgaertel, M. (1990). Rheol. Acta., 29: 535–542.
5.
5. Park, C.P. and Malone, B.A. (1996). US Patent No. 5,527,573.
6.
6. Lee, K.Y., Hong, D., Yoon, K.J., Kim, T.S., Lee, J.H. and Shim, K.H. (2000). Foamplas 2000 Proceedings. 127–140.
7.
7. Abe, S. and Yamaguchi, M. (2001). J. Appl. Polym. Sci., 79: 2146–2155.
8.
8. Krentsel, B.A., Kissin, Y.V., Kleiner, V.I. and Stotskaya, L.L. (1997). Copolymers of Ethylene and Higher-Olefins. In: Polymers and Copolymers of Higher-Olefins, pp. 243–335. Hanser Publishers, Munich.
